CVE-2026-47333

Published May 28, 2026

Last updated 3 months ago

CVSS high 7.8
Ubuntu

Overview

Description
Ubuntu Linux 6.8, 6.17 and 7.0 contain AppArmor SAUCE patches which can potentially incorrectly compute the size of an internal buffer, leading to a heap memory out-of-bounds read in notification handling code. The bug can be triggered by an unprivileged local user and can result in invalid data being processed by the AppArmor DFA policy engine.
Source
security@ubuntu.com
NVD status
Analyzed
Products
ubuntu_linux

Risk scores

CVSS 3.1

Type
Secondary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

security@ubuntu.com
CWE-125

Social media

Hype score
Not currently trending

Configurations

Related CVEs

  1. Google Chromium V8 Type Confusion Vulnerability•CVE-2026-85046
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  3. In the Linux kernel, the following vulnerability has been resolved: mm/percpu-km: fix bitmap overflow and accounting in pcpu_create_chunk() In pcpu_create_chunk(), nr_pages is the total contiguous backing allocation, i.e., nr_units * pcpu_unit_pages, but pcpu_chunk_populated() uses it to set chunk->populated, whose size is pcpu_unit_pages, bitmap. Since bit N in chunk->populated means page offset N inside every unit is backed. When nr_units > 1, the function writes beyond chunk->populated. Fix it by using chunk->nr_pages. It also fixes the global pcpu_nr_empty_pop_pages accounting, since pcpu_balance_free() only iterates up to chunk->nr_pages. Commit a63d4ac4ab609 ("percpu: make percpu-km set chunk->populated bitmap properly") introduced the bitmap overflow issue. Later, commit b539b87fed37f ("percpu: implmeent pcpu_nr_empty_pop_pages and chunk->nr_populated") added pcpu_nr_empty_pop_pages and caused the accounting issue.•CVE-2026-80718
  4. In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: wake linked drain waiters on unlink snd_pcm_drain() on a linked stream parks an on-stack wait entry on the drained peer's runtime->sleep, and after schedule_timeout() removes it only if that peer is still found in the caller's group. If group membership changes during the wait and the sleep ends by signal or timeout (so autoremove_wake_function() does not run), finish_wait() is skipped and snd_pcm_drain() returns with the entry still queued on that stream's sleep list; a later wake_up() then walks a freed stack frame. This is reachable by unlinking either the drained or the draining stream. Unlike the close path (snd_pcm_drop() -> snd_pcm_post_stop()), snd_pcm_unlink() never wakes the sleep queues. Wake every group member under the group lock before the membership change, so a linked drainer is released and drops its entry while the streams are still grouped. The window was opened when snd_pcm_link_rwsem stopped being held across the wait and the removal became conditional on group membership (see Fixes). The later switch to finish_wait() kept that conditional removal, so the signal/timeout case remained.•CVE-2026-80716
  5. In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: ensure no dangling hcon references in iso_conn After iso_conn_del(), ISO sockets should not dereference the hcon any more. Currently, clearing iso_conn::hcon relies on iso_conn_del() releasing the last reference to the iso_conn. Simplify this by explicitly clearing conn->hcon in iso_conn_del(), to avoid more complex reasoning on races about who holds the last reference.•CVE-2026-80721

References

Sources include official advisories and independent security research.